SCHEDULE I - CONDENSED FINANCIAL INFORMATION OF PARENT 3 (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Condensed financial statements
Cash Flows From Operating Activities	$ 96,949	$ 95,145	$ 163,270
Cash Flows From Investing Activities:
Net cash used	(131,221)	(90,138)	(74,059)
Cash Flows From Financing Activities:
Payments for Repurchase of Common Stock	0	(72,893)	(17,180)
Proceeds from stock option exercises	235	1,198	589
Net change in notes payable to banks	62,000	28,000	0
Dividends paid	(33,408)	(32,690)	(32,111)
Proceeds from (Payments for) Other Financing Activities	(1,490)	(957)	(968)
Net cash provided (used)	30,344	(76,631)	(51,449)
Net increase (decrease) in cash and cash equivalents	(3,928)	(71,624)	37,762
Cash and cash equivalents, beginning of year	4,364	75,988	38,226
Cash and cash equivalents, end of year	436	4,364	75,988
AWR
Condensed financial statements
Cash Flows From Operating Activities	34,878	57,682	61,092
Cash Flows From Investing Activities:
Loans (made to)/repaid from, wholly-owned subsidiaries	(64,500)	(12,000)	19,668
Net cash used	(64,500)	(12,000)	19,668
Cash Flows From Financing Activities:
Payments for Repurchase of Common Stock	0	(72,893)	(17,180)
Proceeds from note payable to GSWC	0	20,700	8,300
Repayment of note payable to GSWC	0	(20,700)	(8,800)
Proceeds from stock option exercises	235	1,198	589
Net change in notes payable to banks	62,000	28,000	0
Dividends paid	(33,408)	(32,690)	(32,111)
Proceeds from (Payments for) Other Financing Activities	(9)	(90)	(36)
Net cash provided (used)	28,818	(76,475)	(49,238)
Net increase (decrease) in cash and cash equivalents	(804)	(30,793)	31,522
Cash and cash equivalents, beginning of year	836	31,629	107
Cash and cash equivalents, end of year	$ 32	$ 836	$ 31,629